LE Magazine April 2003
Want to be heart healthy and cancer free? Try cooking your tomatoes
Cooking tomatoes may lower their levels of vitamin C, but there's an apparent payoff in the end. The cooking process substantially increases the levels of healthy compounds known as phytochemicals in tomatoes. So say researchers at Cornell University.1
One of the most well-known phytochemicals found in tomatoes is lycopene, which is the substance responsible for giving tomatoes their red color. Lycopene is a carotenoid that acts as a powerful antioxidant. It is well documented for its cancer-fighting abilities and cardiac benefits. Carotenoids, phenolic acids and flavonoids are grouped together as phytochemicals, which provide the nutritional value in fruits and vegetables. "The research dispels the popular notion that processed fruits and vegetables have lower nutritional value than fresh produce," wrote the researchers.
In the study, tomatoes were heated for various lengths of time, and the scientists confirmed that the longer the heating process, the more vitamin C was lost. Yet, the study also revealed that heating the tomatoes increased levels of beneficial trans-lycopene by 54%, 171% and 164%, respectively, depending on cooking time. Antioxidant levels during the cooking process jumped 28%, 34% and 62%, respectively, as cooking time increased.
Of all the antioxidants in tomatoes, lycopene is the most efficient. It attacks ten times more free radicals in the body than vitamin E. Because the heating process increases lycopene levels in tomatoes, the researchers are hopeful that studies like this may spark a renewed interest in the vegetable. "Ultimately, this could increase consumers' intake of fruits and vegetables and could possibly reduce a person's risk of chronic disease," wrote lead researcher Rui Hai Liu, M.D.
1. Dewanto V, Wu X, Adom KK, Liu RH. Thermal processing enhances the nutritional value of tomatoes by increasing total antioxidant activity. J Agric Food Chem 2002 May 8;50(10):3010-
Study finds even moderate caloric restriction may ward off cancer risk
Limiting caloric consumption-even moderately-may be the key to fending off certain types of cancer, based on the findings of a National Cancer Institute study.
Researchers tested the effects of diets with moderately restricted calories in mice at high risk of developing gastrointestinal cancers. One group ate as much food as they wanted. The second group ate similar types of food, but only 60% of the amount.
The researchers found that the second group of mice still consumed plenty of food, and met all their nutritional requirements, but also had 60% fewer precancerous polyps.
Confirming the old saying that, it's not only how much you eat, but what you eat that matters, the researchers showed that even rodents that ate as much as they wanted had one third fewer polyps, as long as the diet was high in olive oil, fruits and vegetables, compared to those on a high fat diet.
The researchers say that is good news, since olive oil is found in diets typically consumed by humans, and because it's been shown to provide even greater health benefits beyond lowering gastrointestinal cancer risk. The challenge, the scientists noted, is that many people still consume high fat diets and don't take advantage of this benefit.
Increasingly, the scientific literature documents similar findings in terms of the health benefits of caloric restriction1,2,3, including one study that found dietary restriction inhibited a type of malignant brain cancer by nearly 80%, and promoted cancer cell apoptosis in mice.1
1. Mukherjee P et al. Dietary restriction reduces angiogenesis and growth in an orthotopic mouse brain tumour model. Br J Cancer 2000 May 20;86(10):1615-21.
2. Hodgson DM, Chiappelli F, Morrow NS, Taylor AN. Chronic dietary restriction influences tumor metastasis in the rat: parametric considerations. Nutr Cancer 1997;298(2):189-98.
3. Weindruch R, Walford RL, Fligiel S, Guthrie D. The retardation of aging in mice by dietary restriction: longevity, cancer, immunity and lifetime energy intake. J Nutr 1986 Apr;116(4):641-54.
CoQ10's possible new target: migraines
Those who suffer from frequent migraines may find effective relief with a product that science1,2,3 has already suggested may be good for your brain: coenzyme Q10.
A recent study4 tested 150 mg of coenzyme Q10 a day on 32 patients with episodic migraine over four months. At the end of the study period, researchers reported a significant reduction in the number of days that each patient continued to suffer from migraine headaches-plunging from an average of 7.34 days at baseline to just under 3 days by the time the research had concluded. In fact, the study authors discovered that more than 60% of the patients tested experienced greater than 50% reduction in the number of days they suffered with migraines. Those significant results were achieved, they reported, with no adverse side effects.
The authors theorize that coenzyme Q10's efficacy against migraines may be related to the way it targets cellular mitochondrial disorders. Scientists have long suspected that mitochondrial dysfunction may play a role in the development of migraine headaches.
"Mitochondria are the powerhouses of our cells," explained Todd Rozen, M.D., director of Headache Research at the Cleveland Clinic Foundation and the study's lead author. "It's been shown by various investigators… that patients during and in between migraines have a deficiency in brain energy metabolism. There's been some other indirect evidence that that defect is caused by a dysfunction in mitochondria."
The theory is that CoQ10 could be taken as a daily supplement to prevent the onset of episodic migraines, Rozen added. He and his colleagues hope to launch larger controlled studies
1. Piotrowski P, Wierzbicka K, Smialek M. Neuronal death in the rat hippocampus in experimental diabetes and cerebral ischaemia treated with antioxidants. Folia Neuropathol 2001;39(3):147-54.
2. Ebadi M et al. Ubiquinone (coenzyme Q10) and mitochondria in oxidative stress of parkinson's disease. Biol Signals Recept 2001 May-Aug;10(3-4):224-53.
3. Ostrowski RP. Effect of coenzyme Q10 on biochemical and morphological changes in experimental ischemia in the rat brain. Brain Res Bull 2000 Nov 1;53(4):399-407.
4. Rozen TD, et al. Open label trial of coenzyme Q10 as a migraine preventive. Cephalalgia. 2002 Mar;22(2):137-41.
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